Pragmatic Thinking and Learning by Andy Hunt – A great book, packed full of
research and solid advice on improving how you think and learn. Although it's
aimed at software developers, it's accessible and low on jargon. Well worth
picking up.

The 4-Hour Workweek by Timothy Ferris – Worth reading, even if
you're not 100% sold on the idea. The chapter on outsourcing is interesting,
and even if you're not interested in outsourcing your life it's useful to get
used to the idea of delegating tasks.

First Things First by Stephen R. Covey – A good book on time
management that complements "The 7 Habits" well.

Money, Business & Entrepreneurship

The E-Myth Revisited by Michael E. Gerber – Essential reading
for anyone looking to start a business. Explains why people who start
businesses on a technical itch end up failing, and how to solve the problem.

Rework by Jason Fried and David Heinemeier
Hansson – Rework shows you a better, faster, easier way to succeed in
business.

The Accidental Entrepeneur by Susan Urguhart-Brown – For those who
are just beginning to consider starting a venture as well as those who want
to take their organization to the next level, she offers advice on what works
and what doesn't.

The Lean Startup by Eric Ries – The Lean Startup is a new
approach being adopted across the globe, changing the way companies are built
and new products are launched.

The Millionaire Fastlane by MJ DeMarco – An interesting (if
over-materialistic) set of rules for building wealth before you hit
retirement age.